Differentiation of Aedes triseriatus (Say) from Aedes hendersoni Cockerell(Diptera : Culicidae) by restriction fragment length polymorphisms of amplified ribosomal DNA

Aedes triseriatus is the primary vector of LaCrosse (LAC) virus, which can cause encephalitis, especially in young children. Aedes hendersoni, a sibli ng species of Ae. triseriatus, has a salivary gland barrier to LAC virus an d, therefore, is not considered a vector of this virus. Adults of Ae. trise riatus are morphologically indistinguishable from those of Ae. hendersoni, and the two species are sympatric in the eastern United States. A definitiv e method of identifying field specimens is an important part of any disease surveillance program, particularly in the case of LAC virus. This study id entifies restriction enzymes that produce species-specific restriction frag ment length polymorphisms (RFLPs) from amplified ribosomal (r) DNA. In addi tion, sequences of the internal transcribed spacers 1 and 2 and the 5.8S re gions of the rDNA were used to confirm the RFLP patterns. This study is the first to compare nucleotide sequences from Ae. triseriatus and Ae. henders oni.